(1) Field of the Invention
This invention relates to a multifunction-type vibration actuator integrally provided with functions of a speaker, a vibrator, and a buzzer and portable communication equipment mounted with the multifunction-type vibration actuator.
(2) Description of the Related Art
A multifunction-type vibration actuator is integrally provided with a speaker function for sound, a vibrator function for vibration, and a buzzer function for calling to be mounted on portable communication equipment such as a mobile phone and so on. In order to improve spatial efficiency in a device while securing a broad frequency band to keep high tone quality and output, mounting a small-size multifunction-type vibration actuator is desired.
In order to satisfy the requirement, a unit equipped with an elliptic diaphragm that is smaller than a circular diaphragm in width is proposed while keeping almost the same total area See, for example, JP2000-201396A and JP2002-307013A.
The multifunction-type vibration actuator according to prior art is assembled not only with an elliptic housing but also a magnetic circuit part composed of a yoke, a magnet, and a pole piece, as well as a voice coil and a suspension for holding the magnet circuit part, all of which are formed in an elliptic shape.
When an actuator is assembled with parts, all of which are formed in an elliptic shape, the price is high as a multifunction-type vibration actuator because the difficulty in shaping a yoke, a magnet, and a pole piece for the magnetic circuit part results in a high manufacturing cost. In addition, since a housing is totally formed in an elliptic shape, although a lateral space can be saved inside a device, a longitudinal space cannot be saved.